In systems undergoing chemical reaction and diffusion, a remarkable variety of spatially structured patterns, stationary or moving, local or global, can arise, many of them reminiscent of forms and phenomena seen in living systems. Chemical systems offer the advantage that one can often control the parameters that determine the patterns formed and can thereby probe fundamental issues about patt...

Research into the mechanisms of pericyclic reactions continues at a rapid pace. Many of the studies described below address the factors which influence whether a reaction will proceed via concerted rearrangement or will follow a stepwise alternative. Numerous papers published this year report high-level computational studies undertaken to explain unusual regiochemistry or stereochemistry determ...

Computer modeling of enzymes is a valuable complement to experiments. Quantum chemical studies of enzymatic reactions can provide a detailed description of the reaction mechanism and elucidate the roles of various residues in the active site. Different reaction pathways can be analyzed, and their feasibility be established based on calculated energy barriers. In the present thesis, density func...